Abstract:
Water-soluble polyurethane was synthesized by using polyether polyol and diisocyanate as the main raw materials, small molecule diol and methyl pyrrolidone as auxiliary raw materials, and
N-methyl diethanolamine (MDEA) as a hydrophilic chain extender, and the synthesized polyurethane was coated on continuous basalt fibers as a film-forming agent. The properties of water-soluble polyurethane and continuous basalt fibers were studied. The most suitable water-soluble polyurethane was selected as the film-forming agent for the infiltrate. Water contact angle tester, laser particle size analyzer and thermal weight loss analysis were used to study the storage stability, water contact angle, particle size and thermodynamic properties of water-soluble polyurethanes. Fourier infrared spectroscopy, universal testing machine and scanning electron microscopy were used to characterize the chemical elemental composition of continuous basalt fiber surfaces before and after polyurethane treatment. Mechanical properties and surface morphology were also investigated. The continuous basalt fibers before and after the infiltrate treatment were also subjected to acid and alkali treatment to observe the fracture strength retention and mass retention of the fibers. Results showed that when the mass fraction of MDEA (
w(MDEA)) was 6.0%, the waterborne polyurethane had good stability, uniform particle size distribution and ideal water resistance. The fracture strength of continuous basalt fibers treated with sizing agent was increased by 75%, and the toughness was similarly improved. After acid-base treatment, the fiber breaking strength retention and quality retention were significantly increased.